I'm hearing noise around Threads and how it's on their roadmap to implement ActivityPub support, plus suggestions that Threads on the Fediverse is likely to break smaller instances because of the increased level of traffic from a single ActivityPub-enabled instance with 100m+ registered users on it.
I've heard that some instance admins are already considering defederating Threads, although I don't know whether this is because of the potential traffic, or because Meta.
Interesting times.